Electric convenience outlet and contact means therefor



Feb. 24, 1942. J. F. O'BRIEN ELECTRIC CONVENIENCE OUTLET AND CONTACT MEANS THEREFOR Filed Dec. 29, 1939 v INVEN'TOR Jo pl) F. O Brien BY I f um H1 AT al m5 TORNEY Patented Feb. 24, 1942 ELECTRIC CONVENIENCE OUTLET AND CONTACT MEANS THEREFOR Joseph F. OBrien, Jersey City, N. J., assignor to John B. Pierce Foundation, New York, N. Y., a

corporation of New York Application December 29, 1939, Serial No. 311,458

4 Claims.

The present invention relates to electricity connector means, and particularly to electrical outlet means for the reception of attachment plug connectors.

It is an object of the present invention to provide electrical outlet attachment means embodying improved spring metal contacts, secured to electricity conductors in a manner retaining the spring qualities of the metal.

It is another object of the present invention to provide improved spring contact means for electrical outlet device, in which said contact means may be secured to electricity conductor means for soldering, brazing, or like method involving relatively high temperatures, without adversely affecting the springable quality of the contact means.

It is a further object of the present invention to provide electrical contact means adapted to be soldered, brazed, or otherwise secured to electricity conductor means, the solder or like bond between such contact means and the electricity conductor means being disposed remote from the zone of flexure of such contact means, and hence not subjected to strain by the flexure thereof.

The improved outlet connection means embodying the present invention is particularly adaptable for use with an outlet unit in which the body portion is provided with insulating wall means dividing its interior into a plurality of compartments having walls of electrical insulation material. Disposed within said outlet unit, and preferably at the base thereof, are electricity conductors, one such conductor being disposed within each compartment. Suitable apertures, preferably disposed in the plane of the electricity conductors, afford access thereto.

To afford electrical interconnection of the prongs of an electrical attachment plug with the stated conductor means, the present invention contemplates improved spring contact means, desirably comprising a central body portion which is substantially hemi-cylindrical, and having end portions which are of the nature of cylindrical collars having an axial slit. Integral with the central body portion and disposed intermediate said collars and remote therefrom, are provided upwardly extending spring blades. Desirably, the stated spring blades terminate in outwardly and downwardly curving extensions of substantial area.

In attaching the contact means to the conductors, the conductors are passed through the be clamped about the conductors. Such collars thereby substantially completely embrace the conductors, but preferably are so dimensioned as to afford an annular space of capillary magnitude between the collars and the conductor means. The collars may be brazed or soldered to the electricity conductor. Solder is preferred, because capillary flow of the liquid solder into such capillary space insures a strong bond be tween the collars and the conductors. The disposition of the spring blades of the contact means away from the collars, and thus way from the point of application of heat, precludes any substantial transfer of heat from the collars to the spring blades, and prevents a softening or deadening of the spring quality of the metal.

When the conductors and the thereto attached contacts are placed within the body of the connector, the spacing of the outwardly and downwardly curving extensions of such spring blade means being desirably slightly greater than the wall to wall spacing of the respective compartments within which the spring conductors are housed, the extensions bear resiliently against the wall surfaces of the housing. Upon the insertion of an electric outlet plug into the connector, the prongs thereof spread the springable contact elements outwardly against the resistance engendered by the engagement of the spring extensions withthe side walls. Such resistance improves the electricalconnection between the spring contact means and the blades of the outlet plug, and the support afiorded the spring contacts by the housing walls, together with the spacing of the spring blades of the contact means from the collars at which are disposed the areas of securement of the contact means to the conductor means, protects such areas of securement from strain.

Other features and advantages will hereinafter appear.

' In the accompanying drawing:

Fig. 1 is a section taken transversely of an electrical outlet means embodying the present invention;

Fig. 2-is a similar section, but illustrating the action of the prongs of an attachment plug, when in operative position;

Fig; 3 is an enlarged section of a spring contact means, taken along lines 3-3 of Fig. 1; and

Fig. 4 is a perspective of a spring contact means embodying the present invention, as secured to an electricity conductor of the outlet unit.

collars, the axial slits of which permit them to Referring to the drawing, Figure 1 shows so much of an electrical outlet fixture I as is necessary for an understanding of the present invention. Such outlet fixture l0, pursuant to conventional practice, may include a body member l2 of electrical insulation material. Apertures l4 admit the prongs of an attachment plug, and a central insulating wall I6 may divide the body of the outlet means into compartments l8, l8, said compartments being defined by walls of electrical insulation material.

Base portion may be of suitable configuration, but preferably such base portion is provided with longitudinal grooves within which preferably cylindrical conductors 22, 22 may be positioned.

To afford electrical connection of the prongs 24, 24 of an attachment plug 26, see Fig. 2, with the conductors 22, 22, the present invention provides improved spring contact means 28. Such contact means, see Figs. 3 and 4, includes a body portion 30, desirably substantially hemi-cylindrical, at each end of which there is formed a collar 32 having an internal diameter slightly greater than the external diameter of the conductor 22.

Integral with the body portion, and suitably spaced from the respective collars 32, 32, spring blades 34, 34 extend upwardly. Such blades 34 are preferably mutually convergent, and each blade may terminate in an outwardly and downwardly curving wing 38.

As shown in Figure 4, each of the said collars 32 is provided with a longitudinal slit 38, it being desirable to position the slits of the respective collars on'opposite sides of the conductor 22.

To attach a spring contact 28 to a conductor 22, the conductor is passed longitudinally through the respective collars 32, 32. Preferably the clearance between the collars 32 and the conductor 22 is of capillary magnitude. Preferably, the collars 32 are soldered to the conductor 22, the application of the solder to the heated collar being at the respective slits 38. The molten solder will flow, by capillary action, about the circumference of the conductor.

Spring contacts 28 may be stamped from a sheet of cold worked spring bronze or the like.

As is well known, the heating of spring metal to elevated temperatures, such as soldering or brazing temperatures, followed by the cooling of the metal in air, acts to re-orient the grain structure and detrimentally affect the hardness and springability imparted to the metal by the cold working thereof.

In the present invention, however, the spacing of the collars 32 from the spring blades 34 minimizes the transference of heat to the spring blades 34. As is indicated in Figure 3, the body 30 of the contact means 28 preferably has a slight clearance with respect to the conductor 22. Such clearance minimizes heat transfer from the conductor 22 to the spring blades 34 and thus substantially the sole path of heat flow from the collars 32 to the spring blades 34 is about the lower half of the body 30. Th relatively large area of such body 30 rapidly dissipates the heat, and, therefore, the harmful influence of heat upon the temper of the blades 34, is reduced 9. minimum.

The assembled conductor and spring contact may be positioned in the grooves provided in the base portion 20 of the outlet means and the body and base portion of outlet I0 assembled. Desirably, the spread of wings 35 of each contact 28 is greater than the wall to wall spacing of the compartment I8 within which the contact means is housed. Wings 36 bear resiliently against the walls, therefore, and urge the spring blades 34 resiliently toward each other. Upon the insertion of the prongs 24 of an attachment plug into operative association with the contacts 28, the

resultant separation of the spring blades 34,

thereof increases the pressure with which the wings 36 bear against the walls of the outlet. The reaction to such expansion causes the blades 34 to fit tightly against each prong 24 crane-cutof the solder bond, greatly lengthening the effective life of the spring contact means.

Whereas I have described my invention by reference to specific forms thereof, it will be understood that many changes and modifications may be made without departing from the spirit of the invention.

I claim:

1. In combination, electricity connector means including a substantially hemi-cylindrical body, substantially cylindrical collar means secured to said body at the ends thereof, blade-like contact means integral with the said body and extending upwardly therefrom, and electricity conductor means extending axially through said body and said cylindrical collar means and secured to the latter in electricity conductive relationship by soldering or like methods involving elevated temperatures said hemi-cylindrical body means having a diameter greater than that of the conductor means to provide an air space between said conductor means and said hemi-cylindrical body.

2. Electricity connector means comprising the combination with a substantially hemi-cylindrical body, integral collar means disposed at the ends thereof, and spring blade means extending upwardly of said body portion and disposed remote from the collar means, of electricity conductor means passing axially through said collar means and said body and secured to said collar means in electricity conductive relationship by soldering or like methods involving elevated temperatures, said body being in spaced relationship to said conductor to minimize transfer of heat from said conductor to the spring blade means of said body.

3. Electrical outlet means comprising the combination with a body having side wall members of electrical insulation material arranged to define a plurality of compartments, of electricity conductor means extending through said outlet means at the base of said compartments, and contact means disposed within each of said compartments operatively associated with said conductor means, said contact means having collar means encircling said conductors and connected thereto in electricity conductive relationship, by soldering or like methods involving elevated temperatures, body means extending from said collar means and in spaced relationship to said electricity conductors, and blade-like contact means extending upwardly from said body means remote from said collar means.

4. In combination, electricity connector means comprising a substantially hemi-cylindrical body,

collar means formed at an end thereof, bladelike spring contact means extending upwardly from said body portion remote from said collar means, and electricity conductor means extending axially through said collar means and said body portion and secured to said electricity connector means only at said collar means and by methods requiring the application of heat at said collar means, the zone of flexure of said bladelike spring contact means being remote from said collar means to reduce heat transfer from saidcollar means to such zone of flexure and the transfer of flexing strains to said collar means.

JOSEPH F. O'BRIEN. 

